In manufacturing of larger objects, such as matrasses, and furniture adhesives are often applied to fix parts of the large object together. Most adhesives are applied using either air-spray equipment or air-assisted spray equipment.
The present invention relates to using airless-spray equipment and using air-assisted spray equipment. Airless spraying involves using pressure to force a fluid to be sprayed through a small orifice. Airless spray equipment is often operated at lower pressures than air-spray- or air assisted-spray equipment.
Methods and products for applying a layer of adhesive onto a surface wherein the method comprises spraying the adhesive airlessly are known in the prior art.
The prior art methods typically make use of rather complicated equipment. Therein components of adhesives are provided in relatively large containers, e.g., of a few hundred liters. In order to transfer a component from the container to, e.g., a spray equipment pressure is provided to the container, such as air-pressure. Pressure for spraying may be provided by positive displacement pumps, such as double diaphragm pumps or piston pumps; pressurized systems such as pressure tanks; and, gravity feed feeding systems. Such systems are rather voluminous, complex and costly. By providing pressure an adhesive component is typically transferred through a tube or the like to the spray equipment.
As an amount of adhesive used in prior art systems is typically much smaller than a content of a container there is a risk that the component may clog, block a tube, etc. Such requires cleaning of the equipment.
The prior art equipment is typically (somewhat) difficult to handle, e.g., in terms of relocating, and replacing feed stock. It requires typically relative complicated supporting equipment, such as pressure devices, pumps, controls, etc. Also, in view of complexity, such systems are at a certain distance from a location where the adhesive is being applied; inherently such involves some further risks, e.g., clogging of tubing, less control at the location of application, etc.
Some prior art documents recite dispensing systems.
For instance, US2011192864 (A1) recites a system for dispensing polyurethane foam from DOT-39 compliant tank, including a compressor having an outlet through which air is supplied, and a booster coupled to the outlet of the compressor. The booster provides a supply of compressed air at a relatively high pressure of between about 1.1*103 kPa (160) and about 1.38*103 kPa (200 pounds per square inch). This system uses high pressure compressed air to empty 25 liter bladderless tanks (having no liner). The system is used for polyurethane foam, and by providing two containers of which at least one is pressurized a controlled release of polyurethane is obtained. The system is not considered suitable for a two component adhesive.
WO2012071376 (A2) recites disposable dispensers. The dispenser may include a dispense assembly comprising an outlet channel in fluid communication with a terminal apparatus, and a pressure source providing a limited supply of fluid or gas, and also includes a collapsible liner that contains a material to be dispensed, the liner detachably secured to the dispense assembly with the outlet channel in fluid communication with an interior of the liner, wherein the material in the liner is dispensed out the liner and through the outlet channel to the terminal apparatus. The document recites a dispensable pressure source that is limited in supply; such a dispenser is clearly not suited for (semi-)continuous use, as the supply would need to be replaced again and again. The pressure applied is not indicated, but seems to be lower than 10 kPa, in any case a relatively low pressure; hence the system is not considered suited for higher pressures, such as with the present invention and the above document as it may explode. The volume of the system seems to be rather small. Also the goal of this disclosure relates to preventing exposure of the dispensing material and to reduce damage caused by a dispensing material by operating at a low pressure. The dispensed materials relate to pesticides, fertilizer, cleaning solutions, etc. It is preferred not to apply a shear force when applying the dispensing material, as such a force is considered to damage the material.
U.S. Pat. No. 7,021,500 (B1) recites a transportable two-component fluid dispensing kit. The kit includes a container having a front panel and rear panel joined by side panels to form a chamber.
It is therefore an object of the present invention to provide a partly disposable system for a two component adhesive which overcomes one or more of the above disadvantages, without jeopardizing functionality and advantages.